Block’s Indicator of Sustainable Growth

by Ray Block

Good as wind and solar energy can be to provide peak power, they are no substitute to coal fired or nuclear as base load power to provide electricity 24 hours a day. The increasing evidence is that planet earth needs a sharp reduction in carbon pollution, if the disastrous consequences of global warming are to be avoided. The question then arises can geothermal energy become an economic substitute to provide base load energy?

 

Earth Policy Institute (www.earth-policy.org) says a loud Yes. While carbon capture and storage (CCS) can be a large boon allowing a new and vigorous life for a low pollution coal industry. But practical application of this technology is about 10 years away.

 

Even with the likelihood of low carbon coal power, now is the time for geothermal energy to come into its own. Earth Policy Institute says geothermal energy “originating from the earth’s core and from the decay of naturally occurring isotopes such as uranium, thorium and potassium, the heat energy in the uppermost six miles of the planet’s crust is 50.000 times greater than the energy content of all oil and natural gas resources.”

 

Chile, Peru, Mexico, United States, Canada, Russia, China, Japan, Philippines, Indonesia, Papua New Guinea, New Zealand, and other countries with high volcanic activity, encircling the basin of the Pacific Ocean are rich in geothermal energy. The Great Rift Valley of Africa including Kenya and Ethiopia is another geothermal hot spot. As Earth Policy Institute says 39 countries with a combined population of over 750 million have rich geothermal energy resources sufficient to meet all their electricity needs.

 

Outside these countries, where shallow volcanic systems exist and are relatively cheap to exploit, the more expensive hot rock technology in the form of drilling very deep wells up to five Km (three miles), where water is pumped underground, then heated, and the heat energy used to generate power opens the door to many more countries to tap geothermal resources.

 

The “hot rocks” are needed to be 150 degrees Celsius to produce electricity, with temperatures rising the deeper the drill goes into the earth’s crust. In all there are over 70 countries with the capacity to develop geothermal resources for conversion into electricity.

 

Iceland is the model country for renewable energy, with 70 per cent of its energy coming from renewables. Currently, there is 420 MW electricity capacity from two geothermal power stations, sourced from hot rock technology. 27 per cent of the country’s electricity comes from geothermal energy, with the balance coming from hydro power. Iceland has been a pioneer in hot rock technology, and is now the first country in the world to establish a public hydrogen power station, aimed at introducing a hydrogen-based pollution-free traffic system. Hydrogen buses have been extensively tested as an integral part of the Reykjavik public transport system, with Iceland close to its goal of being entirely carbon free.

 

United States has the largest known geothermal resources in the world. The US Geological Survey released in September 2008, the first national geothermal resource survey in more than 30 years, shows an estimated 9,057 MWe of power generation potential from conventional identified geothermal systems. There is also 30,033 MWe of power generation potential from conventional undiscovered geothermal resources.

 

Finally, there is a further 517,800 MWe of power generation potential from unconventional (high temperature, low permeability) enhanced geothermal systems (EGS). The conventional geothermal resources are in the north western part of the US-California, Nevada, Idaho and Oregon, Hawaii, and parts of the north east of New England. The unconventional resources, where hot dry rock or deep geothermal/EGS can be used in almost all of the US, but is particularly applicable in the southern and eastern parts of the country.

 

According to Earth Policy Institute at August 2008, the US had 2,960 MW geothermal installed capacity, with California dominating with 2,555 MW. Most of this capacity is in the Geysers, a geologically active region north of San Francisco. In addition to installed capacity, there are up to 4,000 MW of capacity under development in 13 US states.

 

Outside the US, Philippines ranks No2, generating 23 per cent of its electricity from geothermal resources, and plans to increase it 60 per cent to 3,130 MW.by 2013. Ranking No 3 is Indonesia, which aims to have 6,870 MW of geothermal energy capacity by 2020, at which stage geothermal energy would represent 30 per cent of all energy installed.

 

Europe has little installed capacity, except for Italy, which has 810 MW, and this is expected to double by 2020. Iceland as reported before has 420MW, and Germany an insignificant 8 MW, but is now showing renewed interest in geothermal resources in Bavaria.

 

The disappointing part of this story is that with all the potential that geothermal resources could become as a major part of the globe’s carbon free energy future, it is still largely being pushed aside. Will this change when many more countries introduce an emission trading scheme, and start effectively taxing carbon? That remains to be seen.

 

In countries like the US, where a large part of the geothermal resource is located, geothermal energy from conventional geothermal resources is price competitive with natural gas, and is carbon pollution free. This is not the case with hot rock or deep geothermal/EGS, where a lot of research and money is still needed to bring down the costs of drilling deep wells, where the costs are currently too high.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Posted under Carbon Abatement Scheme, Climate Change, Global Warming, Low Carbon Economy, Renewable Energies